Recording media which are sensitive to light, i.e., a photoresist film on a support, are well known. Such media, when exposed to light containing an information pattern, change their solubility characteristics in those areas exposed to the light pattern. Photoresists are developed by contacting with a solvent which dissolves the more soluble portions, leaving the less soluble portions in a pattern of peaks and valleys which represent the information pattern. Negative photoresists are initially soluble in the developer solution and the exposed portions become insolublized; thus the information pattern is contained inte peaks. Positive photoresists become soluble in the exposed regions, thus the information pattern resides in the valleys.
Recently, suitably modulated electron beams have been substituted for electromagnetic radiation as the recording probe. An electron beam has shorter wavelengths than a light beam, and thus can be more highly focused and record more information in a specific volume. To take advantage of this, a suitable resist should be capable of resolving line widths smaller than the wavelength of near violet light. While some known photoresists are useful as electron beam resists as well, materials which have high resolution and improved sensitivity to electron beams are required for high density recording.